Cable tray systems are structures that are used to support, fasten, and manage cables, tubes, conduit, and wires. Cable tray systems may be used in industry, power generation facilities, manufacturing plants, and the like, and elsewhere where such purposes exist. The cable trays used in these systems often have a U-shaped or an L-shaped cross-section, with the cables, tubes, conduits, and/or wires carried within the U-shape or L-shape. In many applications, it is required that a completed cable tray system have structural rigidity. In other applications, not only is structural rigidity required, but also the completed system must be such that electrical arcing between connected members of the system be avoided should the system become electrically energized.
Cable tray systems typically are constructed of linear runs of trays connected together to span the required length of a given application. Some applications allow for an entire cable tray run to reside in a single plane. However, in other applications, the installation of a run of cable tray may encounter previously-installed obstacles, such as pipes, conduit, or even other cable tray runs, residing in the same plane as the cable tray being installed. In such event, the new cable tray run must be redirected to avoid such an obstacle. In still different applications, for other sufficient reasons, it may be desirable to construct a cable tray system that transitions from one plane to another, even multiple times, along its length.
One prior method of accomplishing such redirection was to require the installer to cut, fit, and attach solid members to work around such an obstacle by deviating above or below it. Such work has been found to be labor intensive and time consuming, and undesirable.
Another method of redirecting a cable tray run is disclosed in U.S. Pat. No. 4,232,845, directed toward a modular support system constructed from a plurality of transportable modular components for assembly into shelves, platforms, ladders, walkways, and other similar structures. The disclosed apparatus provides for vertical displacement of a cable track. However, the apparatus accomplishes such displacement through the use of riser plates of fixed geometry. No pivoting between adjacent sections of a cable track is contemplated, and therefore no range of angular relationships between adjacent runs of cable track may be accomplished.
Yet another method of redirecting a cable tray run is disclosed in U.S. Pat. No. 3,137,468, which discloses a cable tray curve section. While the apparatus of this patent accomplishes a cable track with sections residing in different planes, this redirection is accomplished merely through use of a form section of cable track rather than a pivoting connector. No provision is made for pivoting between adjacent cable track members.
Finally, U.S. Pat. No. 4,432,519 describes a cable mounting ladder for installation to a building or other structure constructed so that curved sections can be interconnected to avoid obstructions in a horizontal plane. The apparatus accomplishes such avoidance, however, with the use of pre-configured, fixed geometry angled interconnectors between adjacent tray members, a labor-intensive, cumbersome system. Furthermore, this device provides for no pivoting between sections of a cable run.
In view of the many advantages of cable track system, and in recognition of the need to avoid interfering obstacles in constructing such a system, it would be desirable to provide a cable tray joint that is adjustable to provide angular redirection of a cable tray run.